package com.hmdp.utils;

import java.util.Map;
import java.util.concurrent.TimeUnit;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.web.servlet.HandlerInterceptor;

import com.hmdp.dto.UserDTO;

import cn.hutool.core.bean.BeanUtil;
import cn.hutool.core.util.StrUtil;
import lombok.extern.slf4j.Slf4j;

/**
 * 拦截任意操作都会触发token刷新
 * 
 * @author 17452
 *
 */
@Slf4j
public class RefreshTokenInterceptor implements HandlerInterceptor {

	private StringRedisTemplate stringRedisTemplate;

	public RefreshTokenInterceptor(StringRedisTemplate stringRedisTemplate) {
		this.stringRedisTemplate = stringRedisTemplate;
	}

	/**
	 * 前置拦截
	 */
	@Override
	public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
			throws Exception {

		log.debug("加载前置拦截器");

		// 1.获取请求头中的token
		String token = request.getHeader("authorization");
		if (StrUtil.isBlank(token)) {
			return true;
		}

		// 2.基于得到的token获取redis中的用户
		String key = RedisConstants.LOGIN_USER_KEY + token;
		Map<Object, Object> userMap = stringRedisTemplate.opsForHash().entries(key);

		// 3.判断用户是否存在
		if (userMap.isEmpty()) {
			return true;
		}

		// 4.将得到的hash数据转为UserDTO对象
		UserDTO userDTO = BeanUtil.fillBeanWithMap(userMap, new UserDTO(), false);

		// 5. 存在，保存用户信息到ThreadLocal
		UserHolder.saveUser(userDTO);

		// 6.刷新token有效期
		stringRedisTemplate.expire(key, RedisConstants.LOGIN_USER_TTL, TimeUnit.MINUTES);
		log.debug("刷新token有效期");

		// 7.放行
		return true;
	}

	/**
	 * 视图渲染后拦截
	 */
	@Override
	public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex)
			throws Exception {
		log.debug("加载视图渲染后拦截器，进行对象销毁~");
		// 移除用户避免内存泄漏
		UserHolder.removeUser();
	}

}
